Scientific and technical programsRisk Mitigation

Jules Verne climatic wind tunnel, CSTB Nantes

Credits: Florence Joubert

Due to climate change, buildings are affected by hazards such as heat waves, wind, storms and snow, which are evolving in terms of frequency and intensity. Meanwhile, innovation is fostering progress in the energy and economic optimization of buildings. Research at the CSTB uses a performance-based approach to reduce the vulnerability of the built environment while taking account of climate trends and technological developments. Here is a close-up on advances in fire safety and climatology.

Improving fire safety

To secure new building techniques, such as insulating from the outside, combustible materials on facades, multistory buildings, etc., the CSTB contributes to progress in controlling the risk of fire spreading on facades. It has published a professional guide on this topic, highlighting reliable construction solutions with respect to these risks for wood buildings. It has also developed a first digital model of the regulatory fire test, LEPIR II.*

More generally, the representativeness of fire resistance studies is increased by taking a hybrid approach: combining in real time a test and the digital modeling of the element being tested in the structure, and adapting the forces during the test, based on the experimental data. This innovative approach will be used for the first time by the end of 2017 at the Vulcain test facility.

Key projects on the scale of components concern the sizing of fasteners exposed to fire, to prevent structural collapse. The CSTB has designed an internationally recognized assessment standard for securing connections using chemical anchors in concrete structures. Research on improved assessments of the actual fire behavior of wood are beginning in 2017.

Deploying wind load engineering

The CSTB responds to requests from foreign stakeholders to study the wind loading of designs for major structures: bridges, stadiums, towers, cultural sites, and more. The ambitious and unique architecture of these structures tends to incorporate sleeker and thinner elements, or larger-scale components, and this makes such structures more sensitive to the effects of weather. The CSTB continually updates its methods to ensure the reliable quantification of the forces exerted on structures, and their sizing. Among other things, these methods rely on digital simulations and testing in the Jules Verne climatic wind tunnel, currently being upgraded to enable a wider range of simulations and tests.

Increasing adaptation to the climate

The CSTB works on devising strategies to adapt buildings and cities to climate change. Heat waves in cities and mitigation techniques have been studied as part of research projects: Muscade and Vurca, with the GAME** and the CIRED, in particular, and Epicea with Météo-France, the APUR and the APC for the City of Paris.

Intense rainfall is also being studied and the CSTB has developed a rain gauge with a high temporal resolution (1 minute). Knowing the profiles of precipitation will benefit the design of green roofs and storm drains. Through this research, the CSTB can propose changes in regulations that apply to the construction of living spaces, in order to keep users safe.

*LEPIR II : 2-level Real Fire Experimental Facility

**GAME : Meteorological Atmosphere Study Group
CIRED: International Environment and Development Research Center
APUR, the Paris Urban Planning Agency APC: the Paris Climate Agency